This an
article showing and explaining how I fitted an LGB MTS decoder
into USA Trains loco. For this article I used a 20t " Mighty Joe
" engine.
This system
works just as well with larger twin motor block locos as well.
Because of the amps these motors pull you will need one decoder
per motor block. For better running add the two motor block
track feeds together so that the decoders receive an input from
both sets of track pickups. This will help over track frogs. But
remember to keep the decoder out puts separate with each decoder
only feeding one motor block.
As the
picture will show this train has a motor block very similar to a
LGB ‘D’ type motor block with four pins, two track pickup and
two for the motor feed, and so I treated it in the same way when
adding an LGB MTS chip.
To be able
to remove the body the motor block runners need to be removed,
this will also allow the motor to be released away from the
body. The whole engine comes apart with the use of a crosshead
screw driver.
Once
motor block and motor runners are removed then you can take out
all the screws that hold the body in place, these include two
under the rear coupling and two very small ones under the motor
block itself which will save the lead weight inside being
removed.
After
gaining access to the inside of the body I then removed the
switch box that the original wiring was connected to. The
functions that these used to control will now be operated direct
from the decoder outputs that will allow these functions to be
operated from the LGB Remote handset.
After looking at what was
left in the way of wiring after removing the switch assembly it
was easier to remove all the internal wiring
from the engine just leaving the two wires that lead from each
light to enable me to connect these all directly to the decoder
itself. I then rewired the loco using the wiring that comes
attached to the decoder its self making things a lot easier than
trying to patch two systems together.
The above
picture shows the decoder in place and the wires running from
decoder under the lead block straight to the motor underneath.
The red and white wires are going straight from the decoder to
the front light and the other wires are leftovers from a direct
decoder fitment in an LGB loco to allow extra length on the
wires so that the rear lights and cab light can reach the
decoder.
Please check
the lights on loco to see if they are fed via a 5volt resistor,
this is normally shown by a small black square item with three
connectors with 5v stamped on it in white, if this is this case
then you will need to reprogram the decoder lighting output to
5v instead of the default 24v setting. This is fairly easy to do
and the best place to look up the values you need to change is
on the LGB website (
www.lgb.com
) you will need either the LGB MTS PC program module of the LGB
MTS Universal Remote Handset No 55015. This only tends to be on
the larger engines as the small ones all seem to be 24v.
There is
always the option to change all the bulbs on the 5v engines with
a pack of LGB 24v bulbs which i have done on many a loco as this
gives a much nicer light that can be be seen better during the
day.
If like
this loco the bulbs are 24volt then wire straight to the decoder
.
The lead
weight has been removed here to show the wiring more clearly.
The extended wires are now simply joined to the original wires
that come direct from the lights and other accessories. In this
model I have not yet got round to putting proper connections in
yet, but there is plenty of room for some crimped terminals at a
later stage I will probably use bullet connections so that the
cab can still be removed at a later date.
As the
next couple of pictures will show there is plenty of room for
the decoder in the main body of the loco and little access
routes for all wiring to be threaded through from and to the
decoder.
On this
model I have only wired up the front and rear lights and the cab
light but there is no reason why all other powered items can not
be connected direct to an LGB MTS decoder such as the smoke unit
or if fitted a sound system, just be careful to check voltage
requirements of these as this decoder give out 24volts which can
be to much for some devices, although the decoder can have its
voltage values changed as per the same procedure for the
lighting outputs explained earlier on in this article.
One thing
I did do on reassembling this train was to make sure that the
motor block and sprung bogie assembly was picking up a track
feed and supplying to the decoder correctly and this meant
checking the red and black wires from the motor and bogie
assembly where correct and not going to cause a short by
bridging the track feed.
this
train has now been running on my railway under LGB MTS control
from about two years now with no signs of running problems or
over heating and all the lights are fully functioning and light
up dependant on train direction just like any LGB MTS equipped
Loco.
If you have
questions or need more details then please feel free to email me
at jason.gscalemad@ntlworld.com
Jason
Palmer. 2005.
